(1) Field of the Invention
This invention relates to hair relaxing compositions for straightening of the hair and, more specifically, relates to improved compositions containing a quaternary ammonium hydroxide.
(2) Prior Art
It is known that the configuration of hair can be altered from curled to straight, for example, by subjecting the hair to the action of a composition which relaxes the hair by rupturing the disulfide bonds in the keratin of the hair to produce free sulfhydryl groups followed by setting with an oxidizing agent. The use of high alkalinity chemicals is also an effective way of modifying the configuration of the hair.
The compositions most commonly used as relaxers are based on sodium hydroxide, sulfite, or thioglycolate. When these products are used to relax the hair, the sulfite and thioglycolate-based products are less effective than sodium hydroxide; thus in the United States the hydroxide is the preferred product for straightening in the salon.
The prior art in an effort to minimize irritation decreased the amount of sodium hydroxide present in hair relaxer compositions. However, compositions having sodium hydroxide in amounts of 3 to 4% are still irritating and further reduction of the concentration in certain oily carriers can result in an ineffective, unpractical product. To further minimize the problems associated with the use of sodium hydroxide containing products the prior art provided for pre-treatment of the hair prior to application of the hair relaxer. In the pre-treatment procedure an oily mixture is deposited on the hair and scalp to form a coating thereon to at least partially shield hair keratin and scalp from the reductive action of the sodium hydroxide.
While the sodium hydroxide and thioglycolate products are irritants and can damage hair, the sulfite products are not effective enough to be permanent relaxers.
A recent development is the use of guanidine hydroxide as a relaxer. However, this product is not stable and must be supplied in two parts; one containing calcium hydroxide and the other quanidine carbonate. The consumer must mix the two parts together prior to being used.
Accordingly, it is an object of the present invention to provide a hair straightening composition that is not as irritating as the sodium hydroxide products.
It is another object of the present invention to provide a composition which does not require mixing to form the active ingredient just prior to its application to the hair.
It is still another object of the present invention to provide a stable formulation in a stable cream base.
It is a further object of the present invention to provide a method for straightening hair in an effective and convenient manner without deleterious effect on the hair and scalp of the user.